Automatic detection of bone marrow infiltration by multiple myeloma detection in low-dose CT

Multiple myeloma is a disease primarily affecting bone marrow. This paper presents a novel method that can automatically detect infiltration of the bone marrow by multiple myeloma in diseased femurs (thigh bones) from low-dose CT images. This detection is done by evaluating two aspects of the CT images: bone marrow infiltrations (increased density values compared to regular fatty bone marrow) and scalloping (indentation of the inner margin of the cortical bone). First, bone marrow and cortical bone are automatically segmented from CT images. Afterwards, a probabilistic model of the bone marrow density is created in order to automatically detect islands of infiltrations. Finally, scalloping is detected by means of the quantification of the roughness of the boundary between the bone marrow and bony tissue. We have experimentally tested both infiltration and scalloping detection methods, obtaining a sensitivity of 74.9% and 69.2% and a specificity of 75% and 61% respectively.